function preloadImage (imgObj, imgSrc) {
 if ( document.images ) {
  eval (imgObj+' = new Image()');
  eval (imgObj+'.src = "'+imgSrc+'"');
 }
}

function changeImage (imgName, imgObj) {
 if ( document.images ) {
  if ( imgName != imgActive ) document.images[imgName].src = eval (imgObj+".src");
 }

 if ( imgObj == 'imgAktivSel' ) {
  if ( imgName != imgActive && imgActive != '' ) document.images[imgActive].src = eval ("imgNoaktiv.src");
  imgActive = imgName;
 }
}

function changeImageEx (layerName, imgName, imgObj) {
 if ( document.images ) {
  if ( dom ) document.getElementById (imgName).src = eval (imgObj+".src");
  else if ( ie4 ) document.all[layerName].document.images[imgName].src = eval (imgObj+".src");
  else if ( ns4 ) document.layers[layerName].document.images[imgName].src = eval(imgObj+".src");
 }
}